Electrochemical cells are desirable for various applications, particularly when operated as fuel cells. Fuel cells have been proposed for many applications including electrical vehicular power plants to replace internal combustion engines. One fuel cell design uses a solid polymer electrolyte (SPE) membrane or proton exchange membrane (PEM), to provide ion exchange between the anode and cathode. Gaseous and liquid fuels are useable within fuel cells. Examples include hydrogen and methanol, with hydrogen being favored. Hydrogen is supplied to the fuel cell's anode. Oxygen (as air) is the cell oxidant and is supplied to the cell's cathode. The electrodes are formed of porous conductive materials, such as woven graphite, graphitized sheets, or carbon paper to enable the fuel to disperse over the surface of the membrane facing the fuel supply electrode. A typical fuel cell is described in U.S. Pat. No. 5,272,017 and U.S. Pat. No. 5,316,871 (Swathirajan et al.).
Important aspects of a fuel cell include reaction surfaces where electrochemical reactions take place, catalysts which catalyze such reactions, ion conductive media, and mass transport media. The cost of power produced by a fuel cell is, in part, dependent on the cost of preparing electrodes and membrane electrode assemblies (MEA). The cost of power produced by a fuel cell is greater than competitive power generation alternatives, partly because of the cost of preparing such electrodes and MEAs. However, power produced from hydrogen-based fuel cells is desirable because hydrogen is environmentally acceptable and hydrogen fuel cells are efficient.
Therefore, it is desirable to improve the manufacture of such assemblies and to improve the cost and render fuel cells more attractive for transportation use.